Some peculiarities of inflorescences morphogenesis in Brexia (Celastraceae)
Abstract
Comparative analysis of inflorescences structure for 6 species of the Brexia (according to the last revision by Schatz & Lowry II (2004)) is conducted. For one species, B. madagascariensis, the shoots growth and development, inflorescence morphogenesis details are studied. It is determined inflorescences of Brexia species (have described in literature as cymes, pseudo-umbellate, corymbiform, sessile in fascicles; and including for some species cauliflory) presents a different variations of ancestral form transformation – dichasial system (closed thyrse). Apparently, presence of a big bracts may be consider as ancestral, plesiomorphic character for the genus; and derivate ones – reduction of bracts and presence of minute bracteoles in pedicel basis only. Inflorescences of Brexia in typically may be considered as bracteous. Process of reduction the number of clusters and separate flowers is accompanied by different variations of their transformations.
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